Washing machine transmission

ABSTRACT

A transmission for a washing machine which uses an off center gear in combination with a rack and pinion mechanism, a brake clutch, and a drive clutch to provide the agitation and the high speed spin of the washing machine. The input shaft is in line with the agitator shaft.

FIELD OF THE INVENTION

This invention relates to a transmission for washing machines and, moreparticularly in the preferred embodiment, top loading washing machines.

BACKGROUND OF THE INVENTION

Washing machines have a transmission located immediately adjacent thetub. Typically, these transmissions produce a back and forth agitatingmovement of an agitator for rotation of the washing machines motor inone direction, with a continuous direct spin of the tub being producedupon the rotation of the motor in an opposite direction. Thetransmission thus provides a dual state operation depending upon thedirection of rotation of the motor for the machine. Typically, thesetransmissions are relatively large and heavy designs having cast ironhousings and complicated interconnections between parts in order toprovide for the agitation movement. The FRANKLIN™ and WHIRLPOOL™ unitsare typical of these designs.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the present invention to provide for a low costtransmission.

It is another object of the present invention to simplify theconstruction of transmissions.

It is yet another object of the present invention to lower the physicalsize of transmissions.

It is still another object of the present invention to reduce the weightof transmissions.

Is is a further object of the present invention to lower to cost andsize of the associated washing machine.

Other objects and a more complete understanding of the invention may behad by referring to the drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS

The structure, operation, and advantages of the presently disclosedpreferred embodiment of the invention will become apparent whenconsideration of the following description taken in conjunction with theaccompanying drawings wherein:

FIG. 1 is a perspective view of a disassembled transmissionincorporating the invention of the application;

FIG. 2 is a longitudinal cross section view of the assembledtransmission of FIG. 1;

FIG. 3 is a lateral cross sectional view of the transmission takensubstantially along lines 3--3 in FIG. 2; and,

FIG. 4 is a second lateral cross sectional view of the transmissiontaken substantially along lines 4--4 in FIG. 2 without counterweight.

DETAILED DESCRIPTION OF THE INVENTION

The transmission of this invention is designed for use with a washingmachine. The washing machine includes a motor and a tub. These are foundin representational form in FIG. 2 as items 8 and 9, respectively. Thetub 9 has a bottom opening 10.

The motor 8 is capable of bidirectional rotation, the direction ofrotation depending upon the allied washing machine control system in thecustomary manner. Upon rotation of this motor 8 in one direction, thetransmission produces back and forth angular agitation of the agitator 7with rotation of the motor 8 in the opposite direction causing spinningof the tub 9. This dual control action is produced by the transmissionfor the washing machine. Some motors also provide variable speeds inaddition to directional control so as to vary the duty cycle. Again,this duty cycle is under the control of the allied washing machinecontrol system.

The transmission 10 of this invention includes a housing 20, anagitation system 60, and an activating system 80.

The housing 20 serves to contain the physical elements of thetransmission. The preferred housing disclosed includes a lower housing21 and an upper housing 22. The lower housing 21 is a deep drawncasting, preferably a low density material such as aluminum, having acavity 25 sufficient to contain the physical parts of the transmission.The lower housing 21 in addition preferably includes an integrallongitudinal extension 26 on the opposite side of the cavity 25 toprovide an extended bearing support. The lower housing 21 also includesa sideways extending lateral cutout 27 for localizing the counterweight(later described). An input tube 30 fixedly connected or integral to theextension 26 provides an interconnection between the frame 100 of thewashing machine, the housing 20 and later described clutch system 81.Two bearings 31 are included on the inside of the input tube 30 forrotatively supporting the later described input shaft 35.

A high mass counterweight 32 is located in the cutout 27 with rubberisolator 33 retaining the counterweight 32 in location. Thiscounterweight 32 is designed to counter balance the otherwiseuncompensated for parts of the housing 20 and agitation system 60 (forexample the eccentric gear 61). Without this counterweight 32, a vastincrease in size and complexity of design for the other parts of thetransmission 10 would be necessary to provide for a smooth balancedspinning of the wash tub 9.

In the preferred embodiment disclosed, the lower casing 21 is also madeof a low density material, aluminum, while the counterweight 32 is madeof a higher density material, steel. This allows for a more effectiveuse the mass of the counterweight 32 than would be possible with similardensity materials. Also, the location of the center of mass of thecounterweight 32 at a significant distance from the rotational axis ofthe transmission 10 further increases its effectiveness regarding lesserdistances. In this respect, also note that in the preferred embodimentthe center of mass of the counterweight 32 is located approximately 50%further outward from the rotational axis of the transmission than thecenter of mass of the furthest item out needing compensation (the gear61 which has its center of mass substantially coextensive with the shaft66). This further increases the effectiveness of the counterweight.

The input shaft 35 is rotatively mounted in respect to the lower housing21 by the bearings 31. This input shaft 35 is axially in line with thelater described agitator shaft 63. This simplifies and strengthens thesupport of the housing 20 to the frame of the washing machine as well asallied drive parts including the tub 9.

A ball 38 between the upper end of the input shaft 35 and the lower endof the agitator shaft 63 locates both such shafts axially in position aswell as providing for a thrust bearing for the later described agitator.As the ball 38 rotates and spins during the operation of the device,wear is spread out evenly over the full outer surface of such ball 38.

A pulley 36 is fixedly connected to the lower end of the input shaft 35for supplying power between the motor 8 and the input shaft 35. Thesizing of this pulley allows for a reduction in relative speed betweenthe motor and the input shaft 35. An input pinion 37 is splined on theother end of the input shaft 35 for drivingly connecting the input shaft35 with the later described eccentric gear 61.

The upper housing 22 completes the housing 20. The upper housing 22consists of a low profile closure member 40 and an extension or agitatortube 41 having a ground 43 outer or exterior surface 42. When the upperhousing 22 is bolted to the lower housing 21 by bolts 42 with the seal43 therebetween, the housing is complete. Two additional bearings 44rotatively support the later described agitator shaft 63 in the agitatortube 41 of the upper housing 22. Again, the upper housing 22 ispreferably made of a low density material such as aluminum so as toincrease the effectiveness of the counterweight 32. As the agitationshaft 63 is in line with the input shaft 35, any inherent rotaryimbalance is eliminated. The careful design techniques, for example thecounterweight 32, further reduce any imbalance.

The agitation system 60 is the mechanism which alters the constantunidirectional rotation of the pulley 36 into a differing direction, aback and forth movement, of the cleansing agitator 7 in the tub 9, thusproviding the necessary cleansing movement for the clothes therein. Thepreferred agitation system disclosed includes an eccentric gear 61, anagitator rack 62, and an agitator shaft 63.

The eccentric gear 61 is rotatively mounted to the housing 20 by anidler shaft 66 which is located extending between holes in the lowerhousing 21 and the upper housing 22. The eccentric gear 61 shown isdirectly rotated by the input pinion 37 which extends off of the end ofthe input shaft 35. The particular input pinion 37 eccentric gear 61gear ratio has an approximate four to one reduction, a reductionsignificantly lower than customary in washing machine transmissions.

A bearing piece 67 extends off of one side of the eccentric gear 61. Thecenter of this bearing piece 67 is displaced from the center of theeccentric gear 61. The side of the bearing piece 67 has a hole 69through it and the rest of the axial depth of the eccentric gear 61 inorder to reduce side to side imbalance forces during rotation (laterdescribed). A raised pie shaped section 68 off of the top of theeccentric gear 61 also aids in reducing this imbalance.

The agitator rack 62 has a circular bearing 70 and a cavity with teeth71 (see FIG. 3). The circular bearing 70 of the agitator rack 62 islocated around the bearing piece 67 of the eccentric gear 61 with thetoothed head 64 of the agitator shaft 63 in driving contact with theteeth 71 of the rack 62. The cavity with teeth 71 is laterally offset inrespect to the circular bearing 70. This reduces vibration by locatingthe longitudinal power transferring axis of the rack of teeth 71 in linewith the central rotational axis of the circular bearing 70 (and shaft66). This is preferred. A small bearing pad 65 extends between thenon-toothed section of the head 64 of the agitator shaft 63 so as tobear on the flat surface 74 of the cavity in the rack 62 on the oppositeside as the teeth 71. This bearing pad 65 has longitudinal slots (dottedlines 73 in FIG. 3) molded into the bottom thereof in order to providefor uniform wall thickness and thus improve cooling. The bearing padfurther has a slight lip 75 formed extending off of the top thereof.This lip 75 cooperates with a small groove 72 formed in the top surfaceof the rack 62 to support the bearing pad 65 in position. Other meanssuch as a groove in the toothed end of the agitator shaft withcorresponding lip for the bearing pad 65, a washer above pinion 37, etc.could also be used to hold this bearing pad 65 in axial position.

The agitator shaft 63 itself is supported by bearings 44 to the agitatortube 41 of the housing 20. The longitudinal rotational axis of theagitator shaft 63 is in line with the longitudinal rotational axis ofthe input shaft 35. This allows the use of a simple ball thrust bearingball 38 as well as simplifying the construction of the remainder of thewashing machine.

During agitation, the housing 20 is fixedly connected to the frame ofthe washing machine (by the later described disc brake assembly 90).This forces the input shaft 35 to rotate in respect to the housing 20.This in turn causes the eccentric gear 61 to rotate. As the eccentricbearing piece 67 has a central rotational axis offset from that of theeccentric gear 61, any rotation of the eccentric gear 61 causes theagitator rack 62 to move back and forth with a reciprocating reversingmovement for a limited longitudinal extent. As the teeth 71 of the rack62 are in driving engagement with the toothed head 64 of the agitatorshaft 63, this mechanism translates the pure rotation of the input shaft35 into a back and forth limited reversing rotational movement of theagitator shaft 63 (about 150° in the embodiment shown). Thistransformation is facilitated by the use of the bearing pad 65 betweenthe toothed head 64 and the flat surface 74 of the rack. The reason forthis is that the bearing pad 65 spreads out the force from the toothedhead 64 over a larger surface than otherwise possible (without thebearing pad 65, there would be direct linear contact between the toothedhead 64 and the flat surface 74, thus concentrating the forces in a verysmall area). This increases wear and reduces durability of thetransmission. The bearing pad 65 reduces friction and wear between theagitator rack 62 and the agitator shaft 63. Note that the toothed head64 could be integral with the agitation shaft.

Due to the use of the preferred design, the amount of mass shifting inthe transmission 10 is reduced relative to other systems. For example ascan be seen in FIG. 3, most of the side to side shifting is caused bythe bearing piece 67 of the eccentric gear 61 and the circular bearing70 of the agitator rack. Due to the hole 69 in the bearing piece 67 andthe narrow width of the circular bearing 70, the effective mass of bothof these parts are minimized. This in combination with the higheffectiveness of the mass of the counterweight 32 and the pie shapedraised section 68 of the eccentric gear 61 (as previously described)reduces off balance rotation. This is particularly so when one considersthe effective mass of the damp clothes in the washing tub during anyspin cycle. The designed in parameters thus lowers vibration relative tocompetitive designs.

The operative condition, agitation, or rotation of the transmission 10is produced by an activating system 80. This activating system 80includes a means of tying the input pulley 36 directly to the housing 20so as to transfer 100% of the rotation of the pulley 36 to such housing20. This causes spinning of the tub 9. A means to interconnect thehousing 20 to the fixed relatively immovable position frame 100 of thewashing machine is also included so as to lock the housing 20 intoposition in respect thereto. This activates agitation by providing areaction lock for the agitation system. As later described, theselective operation of one or the other of these means produces the twooperative conditions for the transmission 10.

In the unpowered condition of the transmission 10, the default conditionis the fixing of the housing 20 to the frame 100 of the washing machineby the later described second clutch means of the brake assembly 90.(This condition is produced by the force of three springs 93 actingdownwardly on a brake disc 91 so as to engage it with a brake surface 92of the frame 100.) This operative condition of the transmission 10remains in effect on rotation of the pulley 36 into an agitationdirection. At this time, the brake assembly 90 provides a reactionmember for the agitation.

On rotation of the pulley 36 in a spin direction, the brake assembly 90is released and the housing 20 tied to the pulley 36 for common rotationby a first clutch means. This operative condition of the transmission 10remains in effect on continuation of rotation of the pulley 36 in a spindirection, reverting to a default condition on cessation of suchrotation.

In the embodiment disclosed in FIG. 1, the two conditions are providedby an inclined ramp clutch assembly 81 and a large disc brake 90. Theparticular clutch assembly 81 disclosed provides for the rotationconnection as well as deactivating the disc brake. It thus is part ofboth means.

The inclined ramp clutch assembly 81 includes an actuation member 82, areaction member 85, a pulley hub 88, and a clutch spring 87.

The pulley hub 88 is fixedly connected to the input pulley 36 forrotation therewith in either direction. This pulley hub 88 has, at itsouter circumference, a unidirectional spiral wound clutch spring 87surrounding it. This clutch spring 87 is spiral wound so as to allowfree rotation of the pulley hub 88 in one direction of rotation whilelocking the pulley hub 88 to the actuation member 82 for rotationtherewith on rotation in the other direction.

The actuation member 82 includes on its upper surface three inclinedramp pockets 86. The reaction member 85 is located immediately above theactuation member 82 with an internal sleeve bearing to the tube of thelower housing 21. Three pockets (not shown) mirror image to those in theagitation member 82 are formed in the lower surface of the reactionmember 85. Note that it is preferred that both these ramp pockets have areduced (or even flat) incline at their shallowest ends. The reason forthis is while the initial spin torque might be high (50 pounds forexample), the continuing spin torque can be a fraction of this (tenpounds for example). As in the preferred embodiment disclosed, there isa substantially 180 pound spring force from the disc brake springs 93,the use of the reduction in incline is utilized to maintain the brake indeactivated condition even during a severe torque drop as long as thepulley 36 continues to be rotated by the motor in a spin direction. Inaddition, the reduction in incline also aids when there are torque loadvariations at a given level (unbalanced loads for example).

Three actuation balls 84 are captured between the ramp of the actuationmember 82 and the pockets of the reaction member 85. These balls 84 actto separate the actuation member 82 from the reaction member 85 on therelative rotation therebetween.

There are a set of overlapping tabs 95, 83 respectively extending off ofthe edges of the reaction member 85 and actuation member 82respectively. These two tabs 95, 83 are designed to solidly drivinglyinterconnect the actuation member 82 to the reaction member 85 at orslightly before the balls 84 contact the shallow end between suchmembers.

With this orientation, relative rotation between the actuation member 82and reaction member 85 in one direction moves the reaction member 85first upwards (via the spring 87 and the balls 84 against the springs93) and then ties the reaction member 85 to the actuation member 82 (viathe tabs 95-83) for rotation therewith. As the reaction member 85 is inturn solidly connected to the housing 20 (via its toothed inner surfaceto the lower end of the tube 30 of the lower housing), this rotation ofthe reaction member 85 also serves to tie the pulley 36 to the housing20 for common rotation (i.e., spin cycle).

The disc brake 91 is deactivated by the upwards movement of the reactionmember 85. The reason for this is the reaction member 85 is fixedlyinterconnected to the disc 91 of the disc brake assembly for commonupwards movement, accomplishing this by the top of the toothed outersurface 89 pushing against member 98. Thus the brake is deactivated asthe actuation member 92 rotates in respect to the reaction member 85.

As rotation of the operative actuation member 82 is provided by theclutch spring 87 interconnection to the pulley hub 88 caused by rotationof the pulley 36 in one direction, the operative condition of theinclined ramp clutch assembly 81 is thus dependent on the direction ofrotation of the motor 8.

The activation of the disc brake 91 serves as the means to causeagitation to occur. This will occur if the motor 8 revolves in anagitation direction. The reason for this is the operation of the discbrake assembly 90.

The disc brake assembly 90 disclosed includes a brake disc 91, a brakering 92, a spring 93, and a reaction member 94.

The brake disc 91 itself is a flat circular member having a brakesurface at its outer lower edge. The inside opening of this brake disc91 is, as previously discussed, interengaged with the toothed outersurface of the reaction member 85 (through part 98) so as to lock thebrake disc 91 to tie such disc 91 to such member 85 for rotation andupward motion therewith. A support member 94 extends between the lowerpart of the housing 20 to a location adjacent to the upper surface ofthe brake disc 91 to bias same into braking condition with the frame viathe springs 93 between the brake disc 91 and the support member 94.These springs 93 serve to bias the brake disc 91 into an actuated orbraked position against the brake ring 92 (180 pounds spring force inthe disclosed embodiment). The brake ring 92 is itself fixedly connectedto the stationary frame 100 of the washing machine.

As the brake disc 91 is fixedly connected to the housing 20 for rotationtherewith in its spring loaded default condition, this serves to lockthe washing machine tub (via a disc 91) into a default braked conditionpreventing the rotation thereof. This activates the agitation mechanismof the transmission.

The inside of the brake disc 91 is positioned next to the upper surfaceof the reaction member 85 such that upward movement of this reactionmember 85 causes the brake disc 91 to move upwards against the force ofthe spring 93 and thus release the brake. In the embodiment shown, thedisc brake assembly 90 is located adjacent to the main lower bearingsupport 96, a fixed part of the washing machine frame, immediatelyadjacent to the main lower bearing 97.

The ramp assembly 86 and brake assembly 90 are activated by thedirection of rotation of the input shaft 35.

Upon rotation of the input shaft 35 and the pulley hub 36 in onedirection, the clutch spring 87 is not activated and the actuation balls84 are located and remain at the lower ends of their ramps in theactuation member 82 and their reaction member 85. This allows the discbrake 91 to continue to contact the brake ring 92, thus holding thelower housing 21 in a position of non-rotation. This provides a reactionmember for the previously described agitation system.

On rotation of the input shaft 35 and the pulley hub 36 in the oppositedirection, the clutch spring 87 is activated tying the actuation member82 to the pulley hub 36 for common rotation. This in turn forces theactuation balls 84 to be moved to the high ends of their respectiveramps in the actuation member 82 and the reaction member 85. This causesthe reaction member 85 to move in an upwards direction. As the brakedisc 91 is located immediately adjacent to the upper surface 95 of thereaction member 85, this movement also forces the disc brake 91 upwardsagainst the force of the springs 93 to move away from the brake ring 92.This releases the brake. When the tabs 83, 95 subsequently contact, thetabs serve to tie the actuation member 82 to the reaction member 85 forrotation therewith. This in turn ties the input shaft 35 to the housing20 for rotation therewith causing spinning of the tub. Therefore, aslong as the pulley 36 (and the shaft 35) continue to rotate in a singledirection, the tub 9 continues to rotate with the shaft. This continuesspinning of the tub 9.

On cessation of rotation of the input shaft 35, the activation mechanismreverts to its default braked condition. This is facilitated by theinertial qualities of the rapidly spinning tub 9 which causes thereaction member 85 to move faster than the actuation member 82, forcingthe balls 84 downwards to the low ends of their ramps thus reactivatingthe brake 90. The incline of the respective pockets facilitates thisreturn to braking condition.

Upon resetting of the brake to its default condition, rotation of theshaft in the first direction will cause agitation of 7, with reverserotation again spinning the tub 9.

Modification of this agitation/spin activation system are possible. Forexample, the two operative conditions are provided by a relative clutchand a relative brake with the activation occurring depending on thedirection of rotation of the pulley 36 in one direction activating theclutch with rotation in a second direction actuating the brake. Othermeans of accomplishing this could be provided.

Although the invention has been described in its preferred embodimentwith a certain degree of particularity, it is to be understood thatnumerous changes can be made without deviating from the invention ashereinafter claimed.

What is claimed:
 1. An improved transmission for a washing machinecomprising a housing, an input shaft, said input shaft having an axis,said input shaft being rotatively mounted to said housing,an eccentricgear, said eccentric gear having rotary axis and an eccentric bearingpiece with a center, said eccentric gear being rotatively mounted tosaid housing with said center of said eccentric bearing piece beingdisplaced from said rotary axis of said eccentric gear, and said rotaryaxis of said eccentric gear being displaced from said axis of said inputshaft, said input shaft being drivingly connected to said eccentricgear, an agitator rack, said agitator rack having a bearing piece and arack, said bearing piece of said agitator rack being connected to saideccentric bearing piece of said eccentric gear, an agitator shaft, saidagitator shaft having an axis and a toothed end, said agitator shaftbeing rotatively mounted to said housing with said axis being in linewith said axis of said input shaft and with said toothed end in drivingcontact with said rack of said agitator rack so as to provide back andforth agitation of said agitator shaft upon rotation of said input shaftrelative to said housing.
 2. An improved transmission for a washingmachine comprising a housing, an input shaft, said input shaft having anaxis, said input shaft being rotatively mounted to said housing,aneccentric gear, said eccentric gear having rotary axis and an eccentricbearing piece with a center, said eccentric gear being rotativelymounted to said housing with said center of said eccentric bearing piecebeing displaced from said rotary axis of said eccentric gear, said inputshaft being drivingly connected to said eccentric gear, an agitatorrack, said agitator rack having a bearing piece and a rack, said bearingpiece of said agitator rack being connected to said eccentric bearingpiece of said eccentric gear, an agitator shaft, said agitator shafthaving an axis and a toothed end, said agitator shaft being rotativelymounted to said housing with said axis being in line with said axis ofsaid input shaft and with said toothed end in driving contact with saidrack of said agitator rack so as to provide back and forth agitation ofsaid agitator shaft upon rotation of said input shaft relative to saidhousing, said agitator rack having a longitudinally extending cavity forsaid rack, said cavity having two sides, said toothed end of saidagitator shaft being located in said cavity with said driving contact tosaid rack being on one side of said cavity, a bearing pad and saidbearing pad being located between said agitator shaft and the other sideof said cavity.
 3. An improved transmission for a washing machinecomprising a housing, an input shaft, said input shaft having an axis,said input shaft being rotatively mounted to said housing,an eccentricgear, said eccentric gear having rotary axis and an eccentric bearingpiece with a center, said eccentric gear being rotatively mounted tosaid housing with said center of said eccentric bearing piece beingdisplaced from said rotary axis of said eccentric gear, said input shaftbeing drivingly connected to said eccentric gear, an agitator rack, saidagitator rack having a bearing piece and a rack, said bearing piece ofsaid agitator rack being connected to said eccentric bearing piece ofsaid eccentric gear, an agitator shaft, said agitator shaft having anaxis and a toothed end, said agitator shaft being rotatively mounted tosaid housing with said axis being in line with said axis of said inputshaft and with said toothed end in driving contact with said rack ofsaid agitator rack so as to provide back and forth agitation of saidagitator shaft upon rotation of said input shaft relative to saidhousing, a balancing means for said eccentric gear, and said balancingmeans balancing said eccentric bearing piece and said agitator rack. 4.An improved transmission for a washing machine comprising a housing, aninput shaft, said input shaft having an axis, said input shaft beingrotatively mounted to said housing,an eccentric gear, said eccentricgear having rotary axis and an eccentric bearing piece with a center,said eccentric gear being rotatively mounted to said housing with saidcenter of said eccentric bearing piece being displaced from said rotaryaxis of said eccentric gear, said input shaft being drivingly connectedto said eccentric gear, an agitator rack, said agitator rack having abearing piece and a rack, said bearing piece of said agitator rack beingconnected to said eccentric bearing piece of said eccentric gear, anagitator shaft, said agitator shaft having an axis and a toothed end,said agitator shaft being rotatively mounted to said housing with saidaxis being in line with said axis of said input shaft and with saidtoothed end in driving contact with said rack of said agitator rack soas to provide back and forth agitation of said agitator shaft uponrotation of said input shaft relative to said housing, said housinghaving a density and being able to rotate about its axis and the centerof the eccentric gear being displaced from the axis of said housing in acertain direction, a counterweight, said counterweight having a densitygreater than the density of the housing, and said counterweight beingconnected to said housing on the opposite side of said housing from saidcenter of said eccentric gear.
 5. An improved transmission for a washingmachine comprising a housing, an input shaft, said input shaft having anaxis, said input shaft being rotatively mounted to said housing,aneccentric gear, said eccentric gear having rotary axis and an eccentricbearing piece with a center, said eccentric gear being rotativelymounted to said housing with said center of said eccentric bearing piecebeing displaced from said rotary axis of said eccentric gear, said inputshaft being drivingly connected to said eccentric gear, an agitatorrack, said agitator rack having a bearing piece and a rack, said bearingpiece of said agitator rack being connected to said eccentric bearingpiece of said eccentric gear, an agitator shaft, said agitator shafthaving an axis and a toothed end, said agitator shaft being rotativelymounted to said housing with said axis being in line with said axis ofsaid input shaft and with said toothed end in driving contact with saidrack of said agitator rack so as to provide back and forth agitation ofsaid agitator shaft upon rotation of said input shaft relative to saidhousing, and said toothed head of said agitator shaft being unitarytherewith.
 6. An improved transmission for a washing machine comprisinga housing, an input shaft, said input shaft having an axis, said inputshaft being rotatively mounted to said housing,an eccentric gear, saideccentric gear having rotary axis and an eccentric bearing piece with acenter, said eccentric gear being rotatively mounted to said housingwith said center of said eccentric bearing piece being displaced fromsaid rotary axis of said eccentric gear, said input shaft beingdrivingly connected to said eccentric gear, an agitator rack, saidagitator rack having a bearing piece and a rack, said bearing piece ofsaid agitator rack being connected to said eccentric bearing piece ofsaid eccentric gear, an agitator shaft, said agitator shaft having anaxis and a toothed end, said agitator shaft being rotatively mounted tosaid housing with said axis being in line with said axis of said inputshaft and with said toothed end in driving contact with said rack ofsaid agitator rack so as to provide back and forth agitation of saidagitator shaft upon rotation of said input shaft relative to saidhousing, said transmission being used with a tub with a bottom opening,said agitator shaft being rotatively mounted to an extension of saidhousing, said extension having an exterior surface, said exteriorsurface of said extension being grooved, the bottom opening of the tubhaving inwardly extending teeth, and the opening of the tub being aboutsaid extension of said housing with said teeth engaging said groovedexterior surface of said extension to drivingly connect the tub to saidextension.
 7. An improved transmission for a washing machine comprisinga housing an input shaft, said input shaft having an axis, said inputshaft being rotatively mounted to said housing,an eccentric gear, saideccentric gear having rotary axis and an eccentric bearing piece with acenter, said eccentric gear being rotatively mounted to said housingwith said center of said eccentric bearing piece being displaced fromsaid rotary axis of said eccentric gear, and said rotary axis of saideccentric gear being displaced from said axis of said input shaft, saidinput shaft being drivingly connected to said eccentric gear, anagitator rack, said agitator rack having a bearing piece and a rack,said bearing piece of said agitator rack being connected to saideccentric bearing piece of said eccentric gear, an agitator shaft, saidagitator shaft having an axis and a toothed end, said agitator shaftbeing rotatively mounted to said housing with said axis being in linewith said axis of said input shaft and with said toothed end in drivingcontact with said rack of said agitator rack so as to provide back andforth agitation of said agitator shaft upon rotation of said input shaftrelative to said housing, a first clutch means to interconnect saidinput shaft to said housing to spin said housing and a second clutchmeans to interconnect said housing to the washing machine to provide areaction member for agitation.
 8. An improved transmission for a washingmachine having an eccentric bearing piece driven reciprocating agitatorrack, such rack having a central longitudinally extending opening havingteeth on one longitudinal side of such opening and a flat surface on theother longitudinal side of such opening,a toothed head of an agitatorshaft being in such opening with teeth in driving connection to theteeth of the opening of the rack and a rounded surface adjacent to theflat surface of the opening of the rack, the improvement of a bearingpad, said bearing pad having two surfaces, and said bearing pad beinglocated between the rounded surface of the toothed head and the flatsurface of the opening of the rack with one said surface engaging therounded surface of the toothed head and the other said surface engagingthe flat surface of the opening of the rack in order to spread out theforces therebetween.
 9. The washing machine transmission of claim 8characterized in that the one said surface of said bearing pad has arounded contour matching that of the rounded surface of the toothedhead.
 10. The washing machine transmission of claim 8 characterized inthat said bearing pad has a top, a lip, said lip extending off said topof said bearing pad, and said lip engaging one of the rack or toothedhead of the agitator shaft in order to retain said bearing pad inposition.
 11. The washing machine transmission of claim 10 characterizedby the addition of a groove, said groove being formed in said one of therack or toothed head, and said lip residing in said groove.